1. Field of the Invention
The instant disclosure relates to an electronic module and method of making the same; in particular, to an electronic module having selective molding and method making the same.
2. Description of Related Art
Conventional electronic module includes a plurality of electronic components disposed on a circuit board. In addition, the electronic component modules may include molding material to encapsulate the electronic components for protection.
However, some electronic components like connectors or optoelectronics are not suitable for encapsulation, for example, the CMOS image sensor (CIS), charge-coupled device (CCD), and light emitting diode (LED). In order to protect some electronic components and remain the function of other components that are not suitable for encapsulation, a “partial molding” is then developed.
Conventional “partial molding” is achieved by mold chase, and the molding material is added to form the molding member. However, because of fluid adhesion, the molding material tends to form air bubbles or void at the mold cavity or the gap between the components and the circuit board. The air bubbles or the voids with moisture and in the following heating process they may cause “popcorn” issue which leads to low yield rate. Furthermore, after molding is completed by the mold chase, the mold chase has to be removed. For removing the mold chase, a draft angle has to be preserved when designing the mold chase. Typically, the acute angle between the mold and the circuit board is approximately 70 degree which reduces the overall usage of the printed circuit board. Moreover, whenever there is a different configuration, such as irregular shape of the molding, the mold chase has to be redesigned. Therefore, the cost is increased and the design consideration of mold chase becomes more complicated.